In `contrib.admin.options.BaseModelAdmin.formfield_for_manytomany` the help_text is reset to `""` because otherwise `ManyToManyField.__init__` would prependo to it 'Hold down "Control", or "Command"...':

7

In `contrib.admin.options.BaseModelAdmin.formfield_for_manytomany` the help_text is reset to `""` because otherwise `ManyToManyField.__init__` would append 'Hold down "Control", or "Command"...' to it: